scott



Filed March 1. 1930 2 Sheets-Sheet By INVflEiNQTg/ZJ May 19, 1931. w. B.SCOTT I 1,806,000

' MOLDING APPARATUS Filed March 4. 1950 2 Sheets-Sheet 2 IN VEN TOR.

BY 5. 5M 7/1fl2 7 A TTORNEY Patented May 19, 1931 UNITED STATES PATENTOFFICE WILLIAM B. SCOTT, F OAKLAND, CALIFORNIA, ASSIG-NOR TO MARCI-IANTSFOUNDRY I ('10., OF OAKLAND, CALIFORNIA, A CORPORATION OF CALIFORNIAMOLDING APPARATUS Application filed March 4, 1930. Serial No. 433,042.

The invention relates to a method and apparatus for fixing a preformedfin or guide Vane element or the like in required position in a castmetal article.

An object of the invention is to provide an improved and particularlyeffective method for fixing a fin or vane in its place in a castingduring the casting process.

Another object of the invention is to provide a method and means forproducing a core to carry said vane for cast-in engagement in thecasting in required relation thereto.

A further object is to provide an improved core box for producing thecore used in otherwise carrying out the invention.

The invention possesses other objects and features of advantage, some ofwhich, with the foregoing, will be set forth or be apparent in thefollowing description of a preferred form of the invention which isillustrated in the accompanying drawings, in which Figure 1 is an endperspective view of a burner element produced through the use of thepresent invention.

Figure 2 is an axial section through a burner assembly utilizing theelement shown in Figure 1.

Figure 3 is a vertical mid-sectional view of a core box of theapparatus, the various core box parts being disposed in their operativerelation to each other and to a plurality of vanes to be incorporated inthe final casting, and an outer portion of the core sand around thevanes is shown rammed in place. Part of the section is taken along thesurface of one of the vanes.

Figure 4 is a view generally similar to that of Figure 3 except that avane-centering element of the apparatus is removed and the core box isshown as completely rammed with the sand.

Figure 5 is a plan and partly sectional view at 55 in Figure 3 withoutany sand in the core box.

Figure 6 is a perspective view of a vane spacer element of the core boxstructure.

Figure 7 discloses face and edge views of a vane for fixing in a castingsuch as that Y portion and discloses a core, formed by use of the corebox, in its operative position in the mold andexposing portions of thevanes for embedment in a casting to be formed in the mold.

The present invention is particularly applied for the production of acast outer nozzle member 11 of a burner 12 for the discharge of fueloilin aerated and atomized form for the combustion thereof, said memberand burner being shown in Figures 1 and 2. As disclosed, the burner 12includes a forwardly opening atomizing cup 13 of cylindrical shape andmounted on a hollow shaft 14 for coaxial rotation within the forward endportion of the nozzle member 11. A relatively fixed drip nozzle 15 atthe end of a pipe 16 through the bore of the shaft 14 discharges at theinner end of the cup cavity whereby the discharged fuel oil forms a filmwithin said cup and is finally discharged tangentially at the outer cupedge 10, the cup cavity being more or less tapered whereby it is largerat said edge. As particularly shown, the shaft 14 is coaxial with thenozzle mem ber 11, and said member is provided with a conically taperedbore through and from which air is arranged to be discharged against theatomized liquid as it leaves the cup 13. The outside of said cup and thebore of the member 11 are cooperative to define an annular dischargepassage 17 for the air, said passage being of symmetrical section withrespect to the nozzle axis whereby the air is distributed uniformlyabout the cup.

For effecting the best mixing .of the discharged streams of air andatomized fuel, it is highly desirable that these streams impinge inmutual opposition, and guide vanes 18 are accordingly provided in thepassage 17. Since the rotation of the cup 13 tends to carry the air inthe passage 17 with it, the .vanes 18 are fixed to the member 11 inunitary and integral association therewith to extend inwardly toward thecup and in such oblique relation to the axis of the assembly that theair emerging from the passage portions between the vanes 18 is directedobliquely against the fiow of the generally fiat and radial stream ofliquid escaping from the cup 13. It is noted that the omission of thevanes 18 would permit an air discharge in the general direction of theflow of liquid and hence minimize both the mixing impact and thefunction of the air stream to direct the mixture forwardly of the nozzleas is required in this type of burner. The inner edges 19 of the vanes18 must closely fit and uniformly clear the outer surface of the cup 13,and must be of a uniform and minimum possible thickness whereby tominimize the obstruction of the passage 17. .The vanes 18 are usually ofsuch thinness that they may not be cast as integral parts of the memberand must be preferably of a different material; in practice, these vanesare desirably about one sixty-fourth of an inch.

The present type of nozzle is well-known in the oil burning art, and inmanufacturing the same it has heretofore been the custom to preform thevanes of thin sheet metal of suitable qualities, such as nichrome steel,cast the outer nozzle member, provide slits in said member extendingfrom the nozzle end, and secure the vanes to the member in its slits asby welding. The latter process is, however, both expensive andinaccurate and requires the truing up of the nozzle at the ni'chromevanes, with a result that the nozzle elements have heretofore beenunreasonably expensive to produce. In accordance with the presentinvention, however, a device is provided whereby the vanes are arrangedto be incorporated in the outer nozzle member as it is cast and in suchrelation thereto as requires no finishing of the completed nozzleelement at the vanes and assures an absolutely accurate and uniformfixed setting of'the vanes. V

Referring now to the apparatus disclosed in Figures 3 to 6 inclusive,said apparatus includes a core box 21 in which to form a core forshaping the bore of a member 11, and a centering element .22 for use ina manner to be hereinafter described. The cavity of the core box 21 isgenerally frusto-conical in shape with the angle of its core that of thebore of the member 11, and so of the core to be formed in the core boxfor producing the bore in the finished casting. The base 23 of the corebox is at the smaller end of its bore, and at and above the point of thecore. box bore which corresponds to the position of the outer ends ofthe vanes 18with respect to the core to be formed, the bore of the corebox is expanded outwardly to provide an annular shoulder 24 which in thepresent instance defines a plane perpendicular to the core box axis.Sets of lining members 25 and 26 are provided for removable andsuperimposed disposal in the corebox and against the wall thereof abovesaid shoulder 24, each set of the said lining members completelyencircling the wall and the inner faces of said members de fining acontinuation of the unexpanded bore portion of the core box whereby theoutline for the core is completely and jointly defined by said membersand said bore portion.

The vane members 18, it will now be noted, are arranged to be preformedas elements from sheet metal of minimum thickness;as stated, a niohromesteel has been found to be particularly desirable material for thepurposes of the nozzle. Since these vanes are arranged to be obliquelyrelated to the axis of the member 11, and their inner edges 19 must liealong or in close proximity to the outer surface of the cup 13, saidedges are concavedly curved longitudinally thereof as is particularlybrought out in Figures 3, 4 and 7. The marginal portion 27 adjacent theouter vane edge28 is arranged for embedment in the member 11, and in thepresent instance in which the outline of said member is frustoconical,said edge is convexedly curved longitudinally thereof. To insure afixing of the vane in the casting, the marginal portion 27 is notched orotherwise perforated to provide for its keying in the cast material ofthe member 11; as shown, dovetail notches 29 are provided along the vaneedge 28. The forward and rear edges 31 and 32 of the vanes are straightand substantially parallel to each other.

The lining members 25, are alike and arranged to receive the outermarginal portions 27 of the vanes between them and to position saidvanes as required in the finished product. \Vith the vanes positioned asrequired, the outer vane edges 28 are arranged to engage along the corebox wall above the shoulder 2 1 while the forward vane edges 31 restagainst said shoulder. In the present instance the edges 31 are arrangedto lie along the face of said shoulder, while the rear vane edges 32define a plane parallel to that of said shoulder; it is noted however,that the shoulder need not be planar. Preferably, and as shown, themembers 25 terminate at the vane edges 32 when the vanes are in place,and the adjacent members 25 of the set thereof are arranged to firmlygrip the vanes between them whereby said-vanes are arranged to be heldfixed in similar set positions and in evenly spaced relation around thecore box wall, the members 25 thus functioning as spacer members for thevanes.

Since the vanes 18 are alike, the described mounting thereof in the corebox so disposes them that the inner vane edges 19 jointly deline acylindrical space corresponding to and slightly larger than the outlineof the cup 13 which is to revolve between them. To insure the definitionof the said cylindrical space, the centering element 22 (Figure 3) isprovided; as shown, said element has an intermediate cylindrical portion33 of thesame outline as the cup 13 and of slightly larger diameter fordefining the aforesaid space between the edges 19 of the vanes. A lowerportion 34 of said element is axially perforated to receive a centeringboss 35 extending upwardly from the base 28 of the core box, while arms36 extend radially from an upper portion 37 of said element forsimultaneous engagement with the lining sections 26, it being noted thatthe lining portions provided by said latter sections are arranged forremoval when desired or required and rests upon and above the positionedvanes and the set of vanepositioning sections 25. A handle 88 is provided on the member 22 for placing and removing the same in itsoperative position.

Having the vanes and core box elements disposed as described and asparticularly shown in Figure 3, core sand 41, preferably containing abonding material, is tamped into place between the element 22 and thecore box bore and about the exposed portions of the vanes 18. When saidsand has been firmed into place, the element 22 is removed and the spacepreviously occupied thereby is filled and packed with more of the sand41 to produce a core 42 as shown in Figures 4 and 8. The core 42 is, asusual, baked before it is used for molding; for baking the core 42, thecore box and core therein may be placed in an oven (not shown) for thepurpose whereby to prevent any drying distortion of the core.

When the core 42 is baked or otherwise set, the core box may be invertedfor the removal of the same from the core in a usual manner. when thecore box is removed from the core, the core lining section 25 and 26remain in position about the core. The lining sections 25 may now beremoved from between the vane marginal portions 27 and the removal ofthe lining sections 26 is the last step in preparing the core for use,it being noted that the core 42 carries the vanes 18 with only theirmarginal portions 27 projecting. The core 42 may now be invested in asand mold 43, as is indicated in Figure 8, whereby to define in part amatrix 44 for filling with molten metal to provide the member 11; saidmolten metal fiowing to and about the vane margins 27 to fix the vanes18 in proper relation in the cast product. In this manner, successivemembers 11 are arranged to be produced with a minimum of labor and aparticularly high degree of uniformity as to the essential relations ofthe parts thereof. It is noted that variation in the obliquity andshapes of the vanes may be readily afi'orded by providing substitutesets of the removable lining members 25 and 26 for the core box.

From the foregoing description taken in connection with the accompanyingdrawings, the advantages of the construction and method of operationwill be readily understood by those skilled in the art to which theinvention appertains, and while I have described the principle ofoperation, together with the device which I now consider to be the bestembodiment thereof, I desire to have it understood that the device shownis merely illustrative, and that such changes may be made, when desired,as fall within the scope of the appended claim.

Having thus described my invention, I claim as new and desire to secureby Letters Patent of the United States, the following:

In molding apparatus for forming a tubular cast member having preformedvanes embedded therein to extend radially within the bore thereof, acore box, lining members in said core box cooperative to engage portionsof said vanes to fixedly dispose the said vanes to extend into the corespace of said box in circumferentially spaced alignment, a centeringelement adapted to be inserted into the core box and engageable with thevanes to maintain them in radial alignment, said centering element beingtapered at its lower end and substantially cylindrical at the portionengageable with the vanes.

In testimony whereof, I afiix my signature.

WILLIAM B. SCOTT.

